Process of dyeing with benzoquinone derivatives.



UNITED STATES PATENT OFFICE.

RUDOLF LESSER, OF BERLIN, GERMANY, ASSIGNOR 'IO FARBWERKE VORM. MEISTERLUCIUS & IBRfi'NING, OF HUCHST-ON-THE-MAIN, GERMANY, A CORPORATION OFGERMANY.

PROCESS OF DYEING WITH BENZOQUINONE DERIVATIVES.

No Drawing.

To all whom it may concern:

Be it known that I, RUDOLF Lnssnn, Ph.

D., chemist, a citizen of the Empire of Germany, residing at Berlin, W.,Germany, have invented certain new and useful Improvements in the'Process of Dyeing with Benzoquinone Derivatives, of which the followingis a specification. My invention relates to a process of dye mg in thevat with certain benzoquinone derivatives, Some of these products arealready known, but their dyeing properties have not been ascertained.The dyestufi's which I found to be suitable for vat dyeing are derivedfrom benzoquinone; they are quinonediarylids which are produced in knownmanner by heating aromatic amins with benzoquinone, its homologues orhalogen derivatives, in an indifferent solvent, such as alcohol, glacialacetic acid or nitrobenzene, with or without addition of a neutralizingagent or catalytic agent.

The constitution of the new products is as follows:

(NHaryD 0 02 by the following example: For dyein with thequinonedianilid, C,H O,(NH H,) (Beilstein 3rd. edition, Vol. 3 page 340)1 kg. of the said dyestufi' is stirred with about 500-1000 liters ofwater and there are then added 10-20 liters of caustic soda lye of- 30B. specific gravit and 20-30 liters of sodium hydrosulfite 0 10 B.specific gravity. On gently heating and stirring the mass, the dyestufi'dissolves and forms an almost colorless vat which yields on cotton orSpecification of Letters Patent.

Application filed February 4, 1911.

Patented Nov. 28, 1911.

Serial No. 606,611.

wool, after exposure to air, yellowish tints. A dyestufi' which yieldsby the same pro cedure brown tints is, for instance, the productobtainable from chloranil and oz-aminoanthraquinone by heating them inpresence of nitrobenzene with addition of copper as a catalytic agent.

Other benzoquinone derivatives dyeing in the vat yellow tints are, forinstance, the chlorodianilidoquinone obtainable from anilin andtrichloroquinone (see Beilstein 3rd edition Vol. III page 340); thechloranildianilid obtainable from chloranil and anilin (see Beilstein3rd edition Vol. III page 343) and also the dyestuft produced fromchloranil and para-anisidin, which forms fine reddish-colored needles ofa metallic luster.

Having now described my invention, What I claim is:

1. The process of dyeing in the vat with benzoquinone derivatives inwhich two hycolor in the usual manner.

In testimon whereof, I affix my signature in presence 0. twowitnesses.

RUDOLF LESSER. Witnesses HENRY HASPER, WOLDEMAR HAUPT.

